An operator of a vehicle traveling on the ground may experience a bumpy ride due to the unevenness of a terrain. The vehicle may transmit the motion arising from the rise and fall of the wheels directly to the operator. To resolve such a problem, certain vehicles are equipped with suspension systems. A conventional suspension system, as shown in U.S. Pat. No. 6,460,318 to Ferris et al., operates by providing a chassis that floats relative to the wheels so that the chassis will be at least partially isolated from the movement of the wheels. However, such suspension systems still cause significant motion of the chassis which in turn is experienced by the operator. Other devices, such as one disclosed in U.S. Pat. No. 5,037,155 to Holm et al., attempt to reduce the transmission of motion by installing a suspension system that spans the base of an operator seat. However, the motion of the vehicle may still be felt by the operator through the legs which feel the movement of the chassis. Thus, there is a need to further isolate the operator from the motion of the chassis and to provide a smoother ride than is realized by existing suspension systems.